<PAGE>   1

                       SECURITIES AND EXCHANGE COMMISSION

                             WASHINGTON, D.C. 20549

                                    FORM 10-Q


[X]     QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES
        EXCHANGE ACT OF 1934

                  FOR THE QUARTERLY PERIOD ENDED JUNE 30, 1999

                                       OR

[ ]     TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES
        EXCHANGE ACT OF 1934

              FOR THE TRANSITION PERIOD FROM ________ TO ________


                         Commission file number 0-21518

                            IEA INCOME FUND XII, L.P.
             (Exact name of registrant as specified in its charter)


            California                                     94-3143940
 (State or other jurisdiction of                        (I.R.S. Employer
  incorporation or organization)                       Identification No.)

         444 Market Street, 15th Floor, San Francisco, California 94111
         (Address of principal executive offices)            (Zip Code)

                                 (415) 677-8990
              (Registrant's telephone number, including area code)


Indicate by check mark whether the registrant (1) has filed all reports required
to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during
the preceding 12 months (or for such shorter period that the registrant was
required to file such reports), and (2) has been subject to such filing
requirements for the past 90 days. Yes [X]. No [ ].



<PAGE>   2

                            IEA INCOME FUND XII, L.P.

                  REPORT ON FORM 10-Q FOR THE QUARTERLY PERIOD
                               ENDED JUNE 30, 1999

                                TABLE OF CONTENTS



<TABLE>
<CAPTION>
                                                                                                      PAGE
<S>      <C>                                                                                          <C>
PART I - FINANCIAL INFORMATION

 Item 1. Financial Statements
         Balance Sheets - June 30, 1999 (unaudited) and December 31, 1998                              4
         Statements of Operations for the three and six months ended June 30,
           1999 and 1998 (unaudited)                                                                   5
         Statements of Cash Flows for the six months  ended June 30, 1999
           and 1998 (unaudited)                                                                        6
         Notes to Financial Statements (unaudited)                                                     7
 Item 2. Management's Discussion and Analysis of Financial Condition and Results of Operations        10
 Item 3. Quantitative and Qualitative Disclosures About Market Risk                                   12

PART II- OTHER INFORMATION
 Item 1. Legal Proceedings                                                                            13
 Item 3. Defaults Upon Senior Securities                                                              13
 Item 5. Other Information                                                                            13
 Item 6. Exhibits and Reports on Form 8-K                                                             14
</TABLE>



                                       2
<PAGE>   3

                         PART I - FINANCIAL INFORMATION


 Item 1. Financial Statements

         Presented herein are the Registrant's balance sheets as of June 30,
         1999 and December 31, 1998, statements of operations for the three and
         six months ended June 30, 1999 and 1998, and statements of cash flows
         for the six months ended June 30, 1999 and 1998.



                                       3
<PAGE>   4


                            IEA INCOME FUND XII, L.P.

                                 BALANCE SHEETS

                                   (UNAUDITED)



<TABLE>
<CAPTION>
                                                                                           June 30,           December 31,
                                                                                             1999                 1998
                                                                                         ------------         ------------
                 Assets
<S>                                                                                      <C>                  <C>
Current assets:
   Cash and cash equivalents, includes $2,008,131 at June 30, 1999
      and $2,407,514 at December 31, 1998 in interest-bearing accounts                   $  2,008,231         $  2,407,614
   Net lease receivables due from Leasing Company
      (notes 1 and 2)                                                                         390,474              656,520
                                                                                         ------------         ------------

         Total current assets                                                               2,398,705            3,064,134
                                                                                         ------------         ------------

Container rental equipment, at cost                                                        62,308,818           62,646,590
   Less accumulated depreciation                                                           24,620,409           23,010,870
                                                                                         ------------         ------------
      Net container rental equipment                                                       37,688,409           39,635,720
                                                                                         ------------         ------------

                                                                                         $ 40,087,114         $ 42,699,854
                                                                                         ============         ============
            Liabilities and Partners' Capital

Current liabilities:
   Accrued expenses                                                                      $    451,367         $    462,948
                                                                                         ------------         ------------

         Total current liabilities                                                            451,367              462,948
                                                                                         ------------         ------------

Partners' capital (deficit):
   General partner                                                                            (90,909)             (64,897)
   Limited partners                                                                        39,726,656           42,301,803
                                                                                         ------------         ------------

         Total partners' capital                                                           39,635,747           42,236,906
                                                                                         ------------         ------------

                                                                                         $ 40,087,114         $ 42,699,854
                                                                                         ============         ============
</TABLE>



   The accompanying notes are an integral part of these financial statements.



                                       4
<PAGE>   5

                            IEA INCOME FUND XII, L.P.

                            STATEMENTS OF OPERATIONS

                                   (UNAUDITED)



<TABLE>
<CAPTION>
                                                              Three Months Ended                        Six Months Ended
                                                        -------------------------------         -------------------------------
                                                         June 30,            June 30,            June 30,            June 30,
                                                           1999                1998                1999                1998
                                                        -----------         -----------         -----------         -----------
<S>                                                     <C>                 <C>                 <C>                 <C>
Net lease revenue (notes 1 and 3)                       $   807,130         $ 1,390,908         $ 1,900,605         $ 2,780,862

Other operating expenses:
   Depreciation                                             915,596             920,906           1,831,492           1,842,132
   Other general and administrative expenses                 24,779              22,960              57,730              51,488
                                                        -----------         -----------         -----------         -----------
                                                            940,375             943,866           1,889,222           1,893,620
                                                        -----------         -----------         -----------         -----------

      Earnings (loss) from operations                      (133,245)            447,042              11,383             887,242

Other income (loss):
   Interest income                                           23,621              30,228              47,574              57,694
   Net income (loss) on disposal of equipment                14,061              (7,738)            (78,624)             (3,242)
                                                        -----------         -----------         -----------         -----------
                                                             37,682              22,490             (31,050)             54,452
                                                        -----------         -----------         -----------         -----------

      Net earnings (loss)                               $   (95,563)        $   469,532         $   (19,667)        $   941,694
                                                        ===========         ===========         ===========         ===========

Allocation of net earnings (loss):
   General partner                                      $    47,419         $    53,873         $    95,966         $   116,675
   Limited partners                                        (142,982)            415,659            (115,633)            825,019
                                                        -----------         -----------         -----------         -----------

                                                        $   (95,563)        $   469,532         $   (19,667)        $   941,694
                                                        ===========         ===========         ===========         ===========

Limited partners' per unit share of net earnings        $     (0.04)        $      0.11         $     (0.03)        $      0.23
                                                        ===========         ===========         ===========         ===========
</TABLE>



   The accompanying notes are an integral part of these financial statements.



                                       5
<PAGE>   6

                            IEA INCOME FUND XII, L.P.

                            STATEMENTS OF CASH FLOWS

                                   (UNAUDITED)



<TABLE>
<CAPTION>
                                                                     Six Months Ended
                                                              -------------------------------
                                                                June 30,           June 30,
                                                                  1999              1998
                                                              -----------         -----------
<S>                                                           <C>                 <C>
Net cash provided by operating activities                     $ 2,025,957         $ 2,811,805

Cash flows provided by (used in) investing activities:
   Proceeds from disposal of equipment                            365,461             328,176
   Purchase of container rental equipment                        (199,342)                 --
   Acquisition fees paid to general partner                        (9,967)                 --
                                                              -----------         -----------

      Net cash provided by investing activities                   156,152             328,176
                                                              -----------         -----------

Cash flows used in financing activities:
   Distribution to partners                                    (2,581,492)         (2,681,426)
                                                              -----------         -----------


Net increase (decrease) in cash and cash equivalents             (399,383)            458,555


Cash and cash equivalents at January 1                          2,407,614           1,883,389
                                                              -----------         -----------


Cash and cash equivalents at June 30                          $ 2,008,231         $ 2,341,944
                                                              ===========         ===========
</TABLE>



   The accompanying notes are an integral part of these financial statements.



                                       6
<PAGE>   7

                            IEA INCOME FUND XII, L.P.

                     NOTES TO UNAUDITED FINANCIAL STATEMENTS


(1)  Summary of Significant Accounting Policies

    (a) Nature of Operations

        IEA Income Fund XII, L.P. (the "Partnership") is a limited partnership
        organized under the laws of the State of California on August 28, 1991
        for the purpose of owning and leasing marine cargo containers. Cronos
        Capital Corp. ("CCC") is the general partner and, with its affiliate
        Cronos Containers Limited (the"Leasing Company"), manages the business
        of the Partnership. The Partnership shall continue until December 31,
        2011, unless sooner terminated upon the occurrence of certain events.

        The Partnership commenced operations on January 31, 1992, when the
        minimum subscription proceeds of $2,000,000 were obtained. The
        Partnership offered 3,750,000 units of limited partnership interest at
        $20 per unit, or $75,000,000. The offering terminated on November 30,
        1992, at which time 3,513,594 limited partnership units had been
        purchased.

        As of June 30, 1999, the Partnership owned and operated 9,268
        twenty-foot, 5,192 forty-foot and 205 forty-foot high-cube marine dry
        cargo containers, as well as 195 twenty-foot and 305 forty-foot marine
        refrigerated cargo containers.

    (b) Leasing Company and Leasing Agent Agreement

        The Partnership has entered into a Leasing Agent Agreement whereby the
        Leasing Company has the responsibility to manage the leasing operations
        of all equipment owned by the Partnership. Pursuant to the Agreement,
        the Leasing Company is responsible for leasing, managing and re-leasing
        the Partnership's containers to ocean carriers and has full discretion
        over which ocean carriers and suppliers of goods and services it may
        deal with. The Leasing Agent Agreement permits the Leasing Company to
        use the containers owned by the Partnership, together with other
        containers owned or managed by the Leasing Company and its affiliates,
        as part of a single fleet operated without regard to ownership. Since
        the Leasing Agent Agreement meets the definition of an operating lease
        in Statement of Financial Accounting Standards (SFAS) No. 13, it is
        accounted for as a lease under which the Partnership is lessor and the
        Leasing Company is lessee.

        The Leasing Agent Agreement generally provides that the Leasing Company
        will make payments to the Partnership based upon rentals collected from
        ocean carriers after deducting direct operating expenses and management
        fees to CCC and the Leasing Company. The Leasing Company leases
        containers to ocean carriers, generally under operating leases which are
        either master leases or term leases (mostly two to five years). Master
        leases do not specify the exact number of containers to be leased or the
        term that each container will remain on hire but allow the ocean carrier
        to pick up and drop off containers at various locations; rentals are
        based upon the number of containers used and the applicable per-diem
        rate. Accordingly, rentals under master leases are all variable and
        contingent upon the number of containers used. Most containers are
        leased to ocean carriers under master leases; leasing agreements with
        fixed payment terms are not material to the financial statements. Since
        there are no material minimum lease rentals, no disclosure of minimum
        lease rentals is provided in these financial statements.



                                                                     (Continued)

                                       7
<PAGE>   8

                            IEA INCOME FUND XII, L.P.

                     NOTES TO UNAUDITED FINANCIAL STATEMENTS


    (c) Basis of Accounting

        The Partnership utilizes the accrual method of accounting. Net lease
        revenue is recorded by the Partnership in each period based upon its
        leasing agent agreement with the Leasing Company. Net lease revenue is
        generally dependent upon operating lease rentals from operating lease
        agreements between the Leasing Company and its various lessees, less
        direct operating expenses and management fees due in respect of the
        containers specified in each operating lease agreement.

    (d) Financial Statement Presentation

        These financial statements have been prepared without audit. Certain
        information and footnote disclosures normally included in financial
        statements prepared in accordance with generally accepted accounting
        procedures have been omitted. It is suggested that these financial
        statements be read in conjunction with the financial statements and
        accompanying notes in the Partnership's latest annual report on Form
        10-K.

        The preparation of financial statements in conformity with generally
        accepted accounting principles (GAAP) requires the Partnership to make
        estimates and assumptions that affect the reported amounts of assets and
        liabilities and disclosure of contingent assets and liabilities at the
        date of the financial statements and the reported amounts of revenues
        and expenses during the reported period. Actual results could differ
        from those estimates.

        The interim financial statements presented herewith reflect all
        adjustments of a normal recurring nature which are, in the opinion of
        management, necessary to a fair statement of the financial condition and
        results of operations for the interim periods presented.


(2)  Net Lease Receivables Due from Leasing Company

     Net lease receivables due from the Leasing Company are determined by
     deducting direct operating payables and accrued expenses, base management
     fees payable, and reimbursed administrative expenses payable to CCC and its
     affiliates from the rental billings payable by the Leasing Company to the
     Partnership under operating leases to ocean carriers for the containers
     owned by the Partnership. Net lease receivables at June 30, 1999 and
     December 31, 1998 were as follows:


<TABLE>
<CAPTION>
                                                                       June 30,        December 31,
                                                                         1999              1998
                                                                      ----------        ----------
<S>                                                                   <C>              <C>
Lease receivables, net of doubtful accounts of
   $163,622 at June 30, 1999 and $209,635 at December 31, 1998        $1,511,921        $1,690,827
Less:
Direct operating payables and accrued expenses                           604,633           491,270
Damage protection reserve                                                237,774           237,855
Base management fees                                                     251,224           271,288
Reimbursed administrative expenses                                        27,816            33,894
                                                                      ----------        ----------

                                                                      $  390,474        $  656,520
                                                                      ==========        ==========
</TABLE>


                                                                     (Continued)


                                       8
<PAGE>   9

                            IEA INCOME FUND XII, L.P.

                     NOTES TO UNAUDITED FINANCIAL STATEMENTS


(3)  Net Lease Revenue

     Net lease revenue is determined by deducting direct operating expenses,
     base management fees and reimbursed administrative expenses to CCC and its
     affiliates from the rental revenue billed by the Leasing Company under
     operating leases to ocean carriers for the containers owned by the
     Partnership. Net lease revenue for the three and six-month periods ended
     June 30, 1999 and 1998 was as follows:

<TABLE>
<CAPTION>
                                              Three Months Ended                    Six Months Ended
                                          ----------------------------        ----------------------------
                                          June 30,           June 30,         June 30,           June 30,
                                            1999               1998             1999               1998
                                          ----------        ----------        ----------        ----------
<S>                                       <C>               <C>               <C>               <C>
Rental revenue (note 4)                   $1,607,095        $2,137,908        $3,469,521        $4,317,266
Less:
Rental equipment operating expenses          585,546           489,908         1,123,244           977,628
Base management fees                         110,702           144,690           238,968           294,592
Reimbursed administrative expenses           103,717           112,402           206,704           264,184
                                          ----------        ----------        ----------        ----------

                                          $  807,130        $1,390,908        $1,900,605        $2,780,862
                                          ==========        ==========        ==========        ==========
</TABLE>


(4)  Operating Segment

     The Financial Accounting Standards Board has issued SFAS No. 131,
     "Disclosures about Segments of an Enterprise and Related Information,"
     which changes the way public business enterprises report financial and
     descriptive information about reportable operating segments. An operating
     segment is a component of an enterprise that engages in business activities
     from which it may earn revenues and incur expenses, whose operating results
     are regularly reviewed by the enterprise's chief operating decision maker
     to make decisions about resources to be allocated to the segment and assess
     its performance, and about which separate financial information is
     available. Management operates the Partnership's container fleet as a
     homogenous unit and has determined, after considering the requirements of
     SFAS No. 131, that as such it has a single reportable operating segment.

     The Partnership derives its revenues from owning and leasing marine cargo
     containers. As of June 30, 1999, the Partnership operated 9,268
     twenty-foot, 5,192 forty-foot and 205 forty-foot high-cube marine dry cargo
     containers, as well as 195 twenty-foot and 305 forty-foot marine
     refrigerated cargo containers. A summary of gross lease revenue, by
     product, for the three and six-month periods ended June 30, 1999 and 1998
     was as follows:

<TABLE>
<CAPTION>
                                    Three Months Ended                  Six Months Ended
                               ----------------------------        ----------------------------
                                June 30,          June 30,         June 30,            June 30,
                                  1999              1998             1999               1998
                               ----------        ----------        ----------        ----------
<S>                            <C>               <C>               <C>               <C>
Dry cargo containers           $1,315,528        $1,722,210        $2,805,445        $3,487,233
Refrigerated containers           291,567           415,698           664,076           830,033
                               ----------        ----------        ----------        ----------

Total                          $1,607,095        $2,137,908        $3,469,521        $4,317,266
                               ==========        ==========        ==========        ==========
</TABLE>

     Due to the Partnership's lack of information regarding the physical
     location of its fleet of containers when on lease in the global shipping
     trade, it is impracticable to provide the geographic area information
     required by SFAS No. 131. Any attempt to separate "foreign" operations from
     "domestic" operations would be dependent on definitions and assumptions
     that are so subjective as to render the information meaningless and
     potentially misleading.



                                       9
<PAGE>   10

Item 2. Management's Discussion and Analysis of Financial Condition and Results
of Operations

It is suggested that the following discussion be read in conjunction with the
Registrant's most recent annual report on Form 10-K.

1)   Material changes in financial condition between June 30, 1999 and December
     31, 1998.

     At June 30, 1999, the Registrant had $2,008,231 in cash and cash
     equivalents, a decrease of $399,383 from the December 31, 1998 cash
     balances.

     The Registrant's operating performance contributed to a 41% decline in net
     lease receivables at June 30, 1999 when compared to December 31, 1998. The
     Registrant's cash distribution from operations for the second quarter of
     1999 was 6.0% (annualized) of the limited partners' original capital
     contributions, a decline from the first quarter of 1999 distribution of
     6.5% (annualized). These distributions are directly related to the
     Registrant's results from operations and may fluctuate accordingly.

     The sentiment with respect to the container industry's slump over the past
     two years has turned more favorable in recent months as evidence suggests a
     turnaround is underway with respect to Asia's economic crisis. In recent
     months, economic reforms in Asia, as well as in Latin America, have begun
     to produce gradual improvement in terms of world trade, and there are
     preliminary indications that containerized trade volumes from North America
     and Europe to Asia, in particular, may be stabilizing. In addition,
     intra-Asian trade, which also has stagnated since the Asia financial crisis
     began nearly two years ago, has shown increased activity in recent months.
     These favorable signs, however, have yet to produce any significant
     positive impact on the Registrant's operating performance. In spite of the
     reduced redelivery of on-hire equipment by the ocean carriers, per-diem
     rental rates, which declined sharply over the past two years, have
     continued to soften as a result of competitive market conditions, decreased
     demand and high inventories.

     The Registrant continues to take advantage of its strong marketing
     resources in order to seek out leasing opportunities during this period in
     which seasonal factors are also influencing the increased demand. At the
     same time, it has identified specific strategies intended to strengthen
     on-hire volumes and enhance utilization of the container fleet. The
     short-term objective is to improve utilization by offering greater leasing
     incentives and actively moving surplus, off-hire equipment to higher-demand
     locations. While this short-term strategy will increase repositioning
     expenses, it may also minimize those expenses related to handling and
     storing off-hire containers. These measures will also provide the
     longer-term advantage of placing the containers where the demand is
     greatest.

2)   Material changes in the results of operations between the three and
     six-month periods ended June 30, 1999 and the three and six-month periods
     ended June 30, 1998.

     Net lease revenue for the three and six-month periods ended June 30, 1999
     was $807,130 and $1,900,605, respectively, a decrease of 42% and 32%,
     respectively, from the same periods in the prior year. Gross rental revenue
     (a component of net lease revenue) for the three and six-month periods
     ended June 30, 1999 was $1,607,095 and $3,469,521, respectively, reflecting
     a decline of 25% and 20%, respectively, from the same periods in the prior
     year. Gross lease revenue was primarily impacted by lower per-diem rental
     rates and utilization levels. Average dry cargo container per-diem rental
     rates for the three and six-month periods ended June 30, 1999 declined
     approximately 6% and 5%, respectively, when compared to the same periods in
     the prior year. Refrigerated container average per-diem rental rates for
     the three and six-month periods ended June 30, 1999 declined 13% and 9%,
     respectively, when compared to the same periods in the prior year.



                                       10
<PAGE>   11

     The Registrant's average fleet size and utilization rates for the three and
     six-month periods ended June 30, 1999 and 1998 were as follows:

<TABLE>
<CAPTION>
                                               Three Months Ended              Six Months Ended
                                            ------------------------       -----------------------
                                            June 30,        June 30,        June 30,      June 30,
                                              1999           1998            1999           1998
                                            ---------      ---------       ---------       -------
<S>                                         <C>            <C>             <C>            <C>
Average fleet size (measured in
   twenty-foot equivalent units (TEU))
      Dry cargo containers                    20,103         20,230         20,116         20,257
      Refrigerated containers                    805            808            806            809
Average Utilization
      Dry cargo containers                        67%            78%            67%            78%
      Refrigerated containers                     68%            84%            69%            85%
</TABLE>

     Rental equipment operating expenses were 36% and 32%, respectively, of the
     Registrant's gross lease revenue during the three and six-month periods
     ended June 30, 1999, as compared to 23% of the Registrant's gross lease
     revenue during both the three and six-month periods ended June 30, 1998.
     This increase was largely attributable to an increase in costs associated
     with slightly lower utilization levels, including handling and storage.

     The Registrant disposed of 46 twenty-foot and 15 forty-foot marine dry
     cargo containers during the second quarter of 1999, as compared to 18
     twenty-foot and nine forty-foot marine dry cargo containers during the same
     period in the prior year. The decision to repair or dispose of a container
     is made when it is returned by a lessee. This decision is influenced by
     various factors including the age, condition, suitability for continued
     leasing, as well as the geographical location of the container when
     disposed. These factors also influence the amount of sales proceeds
     received and the related gain on container disposals.

     Year 2000

     The Registrant relies upon the financial and operational systems provided
     by the Leasing Company and its affiliates, as well as the systems provided
     by other independent third parties to service the three primary areas of
     its business: investor processing/maintenance; container leasing/asset
     tracking; and accounting finance. The Leasing Company's computer systems
     have undergone modifications in order to render the systems ready for the
     Year 2000. The Leasing Company has completed a detailed inventory of all
     software and hardware systems and has identified all components that need
     to be modified. The Leasing Company has completed all the necessary changes
     and testing in a dedicated Year 2000 environment. The Leasing Company
     anticipates that all compliant code will be live by the end of August 1999.
     The Leasing Company has contacted all of its critical business suppliers
     and has been advised that their systems are Year 2000 compliant. The
     Leasing Company has also confirmed the compliance of its suppliers'
     products through its own extensive testing. Expenses associated with
     addressing Year 2000 issues are being recognized as incurred. Management
     has not yet assessed the Year 2000 compliance expense but does not
     anticipate the costs incurred to date or to be incurred in the future by
     the Leasing Company and its affiliates to be in excess of $500,000. None of
     the costs incurred with respect to Year 2000 compliance will be borne by
     the Registrant. The Leasing Company believes it will be able to resolve any
     major Year 2000 issues. The Leasing Company is aware of the implications of
     a Year 2000 computer system failure and is currently in the process of
     developing its contingency plans. While management believes the possibility
     of a Year 2000 system failure to be remote, if the Leasing Company's
     internal systems or those of its critical business suppliers fail, the
     Leasing Company's consolidated financial position, liquidity or results of
     operations may be adversely affected.



                                       11
<PAGE>   12

     Cautionary Statement

     This Quarterly Report on Form 10-Q contains statements relating to future
     results of the Registrant, including certain projections and business
     trends, that are "forward-looking statements" as defined in the Private
     Securities Litigation Reform Act of 1995. Actual results may differ
     materially from those projected as a result of certain risks and
     uncertainties, including but not limited to changes in: economic
     conditions; trade policies; demand for and market acceptance of leased
     marine cargo containers; competitive utilization and per-diem rental rate
     pressures; as well as other risks and uncertainties, including but not
     limited to those described in the above discussion of the marine container
     leasing business under Item 2., Management's Discussion and Analysis of
     Financial Condition and Results of Operations; and those detailed from time
     to time in the filings of Registrant with the Securities and Exchange
     Commission.


Item 3. Quantitative and Qualitative Disclosures About Market Risk

        Not applicable.



                                       12
<PAGE>   13

                           PART II - OTHER INFORMATION


Item 1. Legal Proceedings

        As the Registrant has previously reported, in February 1997, its former
        outside auditors, Arthur Andersen LLP ("Arthur Andersen"), resigned as
        auditors to The Cronos Group (the "Parent Company"), its subsidiaries,
        and all other entities affiliated with the Parent Company, including the
        Registrant. The Parent Company is the indirect corporate parent of CCC,
        the managing general partner of the Registrant. CCC does not believe,
        based upon the information currently available to it, that Arthur
        Andersen's resignation was triggered by any concern over the accounting
        policies and procedures followed by the Registrant.

        Arthur Andersen's reports on the financial statements of CCC and the
        Registrant, for years preceding 1996, had not contained an adverse
        opinion or a disclaimer of opinion, nor were any such reports qualified
        or modified as to uncertainty, audit scope, or accounting principles.

        During the Registrant's fiscal year ended December 31, 1995, and the
        subsequent interim period preceding Arthur Andersen's resignation, there
        were no disagreements between CCC or the Registrant and Arthur Andersen
        on any matter of accounting principles or practices, financial statement
        disclosure, or auditing scope or procedure.

        In connection with its resignation, Arthur Andersen prepared a report
        pursuant to Section 10A of the Securities Exchange Act of 1934, as
        amended, for filing by the Parent Company with the Securities and
        Exchange Commission ("SEC"). As a result of the Arthur Andersen report,
        the SEC commenced an investigation of the Parent Company on February 10,
        1997. The purpose of the investigation has been to determine whether the
        Parent Company and persons associated with the Parent Company violated
        the federal securities laws administered by the SEC. The Registrant does
        not believe that the focus of the SEC's investigation is upon the
        Registrant or CCC.

        Current management of the Parent Company has been in discussions with
        the staff of the SEC with a view to settling the investigation. The
        Parent Company is hopeful of reaching a settlement of the investigation
        by the end of 1999.


Item 3. Defaults Upon Senior Securities

        See Item 5. Other Information.


Item 5. Other Information

        In 1993, the Parent Company negotiated a credit facility with several
        banks for the use by the Parent Company and its subsidiaries, including
        CCC. At December 31, 1998, approximately $33,110,000 in principal
        indebtedness was outstanding under that credit facility (none of which
        had been borrowed by the Registrant). As a party to that credit
        facility, CCC was jointly and severally liable for the repayment of all
        principal and interest owed under the credit facility. On August 2,
        1999, all outstanding amounts under the credit facility were repaid
        through the establishment of a new credit facility with two financial
        institutions. CCC is not a party to the new loan agreement. The Parent
        Company has guaranteed up to $10 million of amounts borrowed under the
        new credit facility and, as partial security for this guarantee, the
        Parent Company has pledged all of the capital stock held by it in Cronos
        Holding/Investments (U.S.), Inc., a Delaware corporation that, in turn,
        owns all of the outstanding capital stock of CCC.

        The Registrant is not a borrower under the new credit facility
        established by the Parent Company, and neither the containers nor the
        other assets of the Registrant have been pledged as collateral under the
        new credit facility.



                                       13
<PAGE>   14

Item 6.  Exhibits and Reports on Form 8-K

(a)  Exhibits

<TABLE>
<CAPTION>
       Exhibit
         No.                       Description                            Method of Filing
         ---                       -----------                            ----------------
<S>             <C>                                                       <C>
        3(a)    Limited Partnership Agreement of the                            *
                Registrant, amended and restated as of December 2, 1991

        3(b)    Certificate of Limited Partnership of the                       **
                Registrant

        10      Form of Leasing Agent Agreement with Cronos                     ***
                Containers Limited

        27      Financial Data Schedule                                         Filed with this document
</TABLE>


(b)  Reports on Form 8-K

     No reports on Form 8-K were filed by the Registrant during the quarter
ended June 30, 1999.

















---------

*       Incorporated by reference to Exhibit "A" to the Prospectus of the
        Registrant dated December 2, 1991, included as part of Registration
        Statement on Form S-1 (No. 33-42697)

**      Incorporated by reference to Exhibit 3.2 to the Registration Statement
        on Form S-1 (No. 33-42697)

***     Incorporated by reference to Exhibit 10.2 to the Registration Statement
        on Form S-1 (No. 33-42697)



                                       14
<PAGE>   15

                                   SIGNATURES


        Pursuant to the requirements of the Securities Exchange Act of 1934, the
Registrant has duly caused this Report to be signed on its behalf by the
undersigned thereunto duly authorized.




                                            IEA INCOME FUND XII, L.P.


                                            By Cronos Capital Corp.
                                               The General Partner




                                            By /s/ Dennis J. Tietz
                                               ---------------------------------
                                               Dennis J. Tietz
                                               President and Director of Cronos
                                               Capital Corp. ("CCC")
                                               Principal Executive Officer of
                                               CCC




Date: August 16, 1999



                                       15
<PAGE>   16

                                  EXHIBIT INDEX



<TABLE>
<CAPTION>
       Exhibit
         No.                       Description                            Method of Filing
         ---                       -----------                            ----------------
<S>             <C>                                                       <C>
        3(a)    Limited Partnership Agreement of the                            *
                Registrant, amended and restated as of December 2, 1991

        3(b)    Certificate of Limited Partnership of the                       **
                Registrant

        10      Form of Leasing Agent Agreement with Cronos                     ***
                Containers Limited

        27      Financial Data Schedule                                         Filed with this document
</TABLE>














---------

*       Incorporated by reference to Exhibit "A" to the Prospectus of the
        Registrant dated December 2, 1991, included as part of Registration
        Statement on Form S-1 (No. 33-42697)

**      Incorporated by reference to Exhibit 3.2 to the Registration Statement
        on Form S-1 (No. 33-42697)

***     Incorporated by reference to Exhibit 10.2 to the Registration Statement
        on Form S-1 (No. 33-42697)